The fire in a disused church in Amsterdam on New Year’s Eve was framed as an attack by Muslim terrorists minutes after the event through a note widely shared on social media, according to a report by extremism monitoring body Justice for Prosperity.

The fire at the Vondelkerk, the cause of which is still being investigated by the police and fire services, was laid at the door of “Jihadists” and “Muslim terrorists” and also involved the “leftwing elite”, according to the messages. The blaze took place during the annual firework frenzy.

The story is part of a “targeted disinformation campaign”, the organisation’s director, Jelle Postma, who is a former member of Dutch security service AIVD, told broadcaster NOS.

Some 20% of messages that appeared on X following the fire linked it to Muslims, he said and the story was shared on TikTok and Telegram as well.

“Just minutes after the news about the fire broke, we saw the first false claims. Suggestions such as “could this be a Muslim terrorist attack” became a statement of fact within an hour,” Postma said. They were quickly taken up by influential far right activists such as Eva Vlaardingerbroek and Tommy Robinson.

“From then on, the snowball turned into an avalanche,” Postma said. The association with jihadism and a left-wing elite is “remarkable”, he said, because the two are not very often linked in the Netherlands.

The story was also picked up by pro-Kremlin media and Russian influencers, as happened with the Malieveld anti-immigration riots. “Local incidents are picked up and polarised as part of the disinformation campaign, Postma said.

False claims are difficult to combat, he said, and in the case of the Vondelkerk fire, it will be many months before the cause is established.

No miracle cure

According to political communications expert Claes de Vreese, algorithms that reward disinformation should be restricted. Warning labels should also be attached to say a story hasn’t been verified, he said.

However, there is no “miracle cure” for disinformation, he said. “Content can be moderated but as long as there is an incentive to spread disinformation, it will continue.”

More research is needed into the networks that spread false information, Postma said. “The argument is that this is freedom of speech but in fact it is undermining democracy,” he said. A social debate about the limits of free speech, he said, is necessary ”to protect democracy from itself”.